Using regex in UI for Log Format field in order to filter log content


Is it possible to embed a VCL regex into the “Log Format” field in the UI in order to strip out content from a field.

For example, can I create an entry such as

“%t”,"%{req.http.Cookie}V","%{resp.http.Set-Cookie}V","%{regsub(req.postbody, "da_password_field=.* “,“PASSWD”)}V”

It passed the validation and looked fine in the VCL, but I stopped getting content into my S3 logs and before I stressfully debug this I wanted to verify that it is kosher to embed the regex like this without doing Custom VCL for logging.


Based on some testing, it looks like this works. In case anyone else stumbles across this they will have some validation that this works if you have the proper syntax.